The present invention relates to improvements in head sets for bicycles, and more particularly in dustproof and waterproof type head set arrangements.
Bicycle head sets must be smoothly turnable for steering. However, the prior art arrangement has disadvantages in that dust or water may enter it from between a bottom ball head cup and a crown ball race and/or a top ball head cup and a screwed ball race (top cone). Thus bearing parts or other ball-abutting parts undergo rusting and wearing which have an adverse influence on the turning and steering capacity of handlebars. To avoid this, it has been proposed to use sealed bearings. Such a proposal is undesirable, however, since the height and weight of a hanger set would be increased. Increases in height and weight go against a current trend toward reducing the size and weight of parts as much as possible.